Questions tagged [igmp]

For questions about IGMP (Internet Group Management Protocol), a protocol used for communications between IPv4 hosts and multicast routers to establish and maintain host multicast group membership.

Filter by
Sorted by
Tagged with
1 vote
1 answer
140 views

IGMP in multiple switches with multiple Senders and Receivers in same VLAN

I am trying to send multicast traffic from 3 Senders to corresponding Receivers in same VLAN (100) spread across 3 switches. I setup a Querier in one of the switch, but it doesn't seem to forward ...
user avatar
  • 63
2 votes
2 answers
153 views

Query regarding IGMP Querier Election Process

I wanted to understand how a querier election takes place. Say we have to L3 devices with ip address 10.1.1.2 and 10.1.1.1. PIM is not enabled anywhere. I checked around and found that the flow would ...
user avatar
0 votes
1 answer
89 views

PIM-SM over OSPF for mDNS traffic

I have connected 2 Routers via OSPF (using N links, N == 1 but it should be scalable to N > 2) and I am trying to have mDNS traffic go from LAN to LAN across the OSPF link, but I can't seem to make ...
user avatar
0 votes
0 answers
48 views

Does multicast over tunnels (e.g., GRE) require IGMP/MLD?

When subscribing to a multicast group on a tunnel device such as a GRE tunnel, are you supposed to participate in IGMP/MLD over that tunnel in order to announce your membership in the multicast group? ...
user avatar
  • 317
1 vote
0 answers
174 views

Multicast traffic through Cisco3850

I have a test scenario and trying to pass multicast traffic through Cisco 3850 according to the following diagram: ![enter image description here MC source: several MC IPs such as 232.0.26.0, 232.0.27....
user avatar
  • 11
0 votes
1 answer
83 views

What prevents a device from receiving its own multicast stream, and can it be turned off?

I know that it is normally not possible for a device to receive its own multicast stream on the same network interface where it transmitted said stream. I also understand why this is sensible, and ...
user avatar
2 votes
1 answer
105 views

In an IGMP V2 membership report message, isn't the destination Ethernet address based on the multicast group IP address?

Specifically, I think for this message type the Ethernet destination address always starts with 01:00:5E, followed by the second byte of the IP address masked with 0x7F, followed by the third and ...
user avatar
2 votes
0 answers
272 views

IGMP Snooping issue. probably

I have multicast hosts that keep leaving a group, only to join back up which results in loss of video feeds. The network consists of a variety of Cisco 2960's and a Cisco 9300 w/ PIM Sparse mode set ...
user avatar
  • 21
0 votes
1 answer
643 views

How to enable Inter-VLAN multicast traffic on a layer 3 Siemens RX1510 Network Switch using IGMP?

I have a single Layer 3 Siemens RX1510 network switch split into 4 separate VLANs on different subsets. Name | Gateway | Subnet VLAN1 | 198.97.100.123 | 255.255.255.0 VLAN2 |...
user avatar
2 votes
2 answers
210 views

Trying to understand IGMPv3 Max Response Code algorithm

In IGMPv2, the Max response time is an 8-bit value each unit encoding 0.1 seconds. The typical max response time is 100 resulting in a 10 second max response time. In IGMPv3, if the Max response code ...
user avatar
  • 2,083
2 votes
1 answer
90 views

How can MLDv2 work according to the RFCs 3810 and 4606?

When IPv6 Stateless Address Autoconfiguration is happening, an interface/node has to join the all-nodes multicast address and the solicited-node multicast address AFTER forming a "tentative" ...
user avatar
0 votes
1 answer
361 views

Multicast in one VLAN

I need to receive multicast traffic over L2 segment on my client machine. But for some reason I am unable to do it. To my understanding with such scheme I should receive traffic if inbetween Juniper ...
user avatar
  • 45
1 vote
0 answers
234 views

To multicast or not to multicast over LTE? [closed]

I have an IOT device with static IP connected to a Mikrotik LTE device on ether1. The IOT host sends a multicast packet every second. The packet contains the IP and MAC of the host. IP-Multicast: ...
user avatar
  • 111
2 votes
1 answer
89 views

IGMP leave group

Would like to have some clarification on following scenario: There is Linux platform with an Ethernet interface which has some constant default IP address (eth0: 10.0.0.1) and some changing IP ...
user avatar
7 votes
3 answers
5k views

OSPF and its use of Multicast

When it comes to OSPF and its use of multicast, am I correct in believing that IGMP forwarding and an IGMP querier is still required within the local segment? My understanding would be without this, ...
user avatar
  • 269
1 vote
1 answer
351 views

Understanding IP multicast in linux [closed]

My ultimate goal is to setup IGMP snooping on a linux machine using netfilter hooks. This is for exploratory purposes to understand IGMP protocol. The topology we are using is as follows: | ...
user avatar
  • 111
3 votes
1 answer
2k views

Using IGMP but Multicast still Flooding

Im new here. I want to ask about the multicast, The first case is, I have switch HP 2530 24 port with 24 10/100 and 2 100/1000 NIC, And i have servers with bandwidth video multicast around 120-...
user avatar
  • 33
3 votes
1 answer
2k views

Multicast flooding network ProCurve Switch 2520G

Switch: ProCurve Switch 2520G-8-PoE Scenario: Multicast is flooded onto the network Having multicast flooded makes it so TV is stuttering and pixelating. I do on my ProCurve have IGMP and Querier ...
user avatar
  • 55
4 votes
3 answers
899 views

Multicast routing on Huawei Quidway 5300 Switches

I have been testing a scenario which involves multicast routing for multicast traffic the scenario is pretty simple. I have two L3 switches with OSPF running in between them, two computers are ...
user avatar
  • 43
2 votes
2 answers
6k views

Aruba 2530 - IGMP Enabled, Querier on still no filtering

I have a in port 1 - 5 channels of multicast. On port 2 i have a computer. Both are in VLAN 10 untagged and a more bigger network tagged on port 3. I've enabled IGMP with: config, vlan 10, ip igmp, ...
user avatar
  • 55
3 votes
2 answers
4k views

IGMP and multicast forwarding

So my question is, will using IGMP alone(without IGMP snooping, PIM...etc) making router forwarding multicast traffic? I'm working on a buggy switch, but I don't know about networking too, so I'm ...
user avatar
  • 131
3 votes
0 answers
387 views

STB generate IGMP Leave without reason

In my network STB generates IGMP Leave (in STB logs "End of Stream") without any reason or there is something what I don't understand. There is one exeption STB directly connected to PIM (ASR920) ...
user avatar
  • 71
3 votes
2 answers
9k views

Multicast between VLANs

I've following scenario Upper computer on VLAN 10 is sending some multicast messages and lower computer on VLAN 10 sends IGMP join periodically. Lets say MC address is 224.1.1.1 Now, computer on ...
user avatar
4 votes
0 answers
242 views

ASR920 - port Te0/0/3-tefp1 is not a router port on Vlan 217

When I enabled debugging: PIM#debug ip igmp snooping router I get in logs: Mar 30 15:58:36.275: IGMPSN: router: port Te0/0/3-tefp1 is not a router port on Vlan 217 Configuration for interfaces: ...
user avatar
  • 71
2 votes
1 answer
63 views

Should igmp table lookup misses flood to all ports?

With igmp snooping, upon receiving a multicast packet it looks up the table and decides which ports to forward the packet. What I'm wondering is, if there is not an entry in the table for that ...
user avatar
  • 123
1 vote
1 answer
189 views

Question Regarding IGMPv3 behaviour: Multicast Router appears to send Membership Report?

I'm new to how IGMP works. Recently, I was looking at a packet capture: I see that 172.18.1.3 sends a membership query to the all hosts address, leading me to assume that 172.18.1.3 is a multicast ...
user avatar
2 votes
1 answer
1k views

Rationale for EXCLUDE mode in mutlicast IGMPv3 / MLDv2

Both IGMPv3 and MLDv2 have an include and an exclude mode, where a multicast listener can specify to either listen only for packets from some list of source addresses (include) or only for packets ...
user avatar
  • 121
2 votes
1 answer
2k views

IGMP snooping across VLANs

Set up: Core switch: C1 C1 is an L3 switch--there is no router Access switches: A1, A2, A3 VLANs: V1, V2 Hosts: H11, H12, H13, H21, H22, etc. Connections: C1 connects to A1, A2, A3 A1, A2, A3 each ...
user avatar
0 votes
3 answers
2k views

Minimum possible size of Ethernet/IGMP frames

I am writing an application that needs to ignore frames whose size is smaller than the minimum possible size of Ethernet/IGMP frames. I have researched extensively and found the following information: ...
user avatar
2 votes
1 answer
805 views

Unable to route multicast from IPcam (four vlans, one switch, one router with router-on-a-stick)

Okay, so I've been searching far and wide for a solution to my problem here. I want to be able to access an IPcam through its respective software across VLANs. Hardware: Cisco 1841 Router, firmware ...
user avatar
  • 23
4 votes
1 answer
2k views

Multicast timer expires

I've a multicast network for security cameras (multiple RPs, bsr, connectivity with OSPF). The problem is that the monitors sometimes stop receiving the video stream. (10.0.0.1, 234.0.0.1), 00:10:11/...
user avatar
  • 383
3 votes
0 answers
3k views

Regarding vPC Dual Active or Split Brain scenario

Consider the below topology: Imagine that both the vPC peer keepalive link and vPC peer link have gone down. I am trying to understand how will that lead to unpredictable traffic flows or loops. ...
user avatar
  • 859
4 votes
1 answer
983 views

Multiple VLANs under one subnet (for traffic control)

Looking at a fiber ring network of 11 switches on the same subnet, with 3 types of devices per module (device 1, 2 & 3). control room switch 192.168.11.100 module 1 ethernet switch 192....
user avatar
  • 141
1 vote
1 answer
439 views

Cisco 4948 - multicast routing

Could anyone help me with Cisco 4948 config? I have to route multicast traffic from one Vlan to another. Multicast source and multicast destination are IGMP-enabled devices, there are no PIM-devices ...
user avatar
3 votes
2 answers
715 views

How do you disable IGMP-snooping on virtual nic macvtap

Networking community, Question: How do you disable IGMP-snooping on virtual nic macvtap? Background: We have noticed that Juniper vSRX 15.1X49-D60 (Running on Ubuntu 16.04LTS Server KVM) is ...
user avatar
1 vote
1 answer
550 views

IGMP and Multicast

I have 3 hosts (h1, h2, h3) on my LAN segment and a router with IGMP enabled. Now the host h3 wants to join the multicast group (239.0.0.2 say) Host h3 will send a membership report to 239.0.0.2 (...
user avatar
  • 859
5 votes
3 answers
13k views

Inter-switch IGMP on a VLAN with two switches, and a multicast source per switch

I have a network consisting of two HP 2810 switched. Attached to each switch is, on one port, a multicast video coder, and on a different port, a decoder. There are two VLANs - a control VLAN (...
user avatar
3 votes
0 answers
1k views

How do switches behave on multicast? [closed]

I am benchmarking multicast throughput of my LAN using an application that considers all the servers as group members. The network consists of homogeneous servers (S0-S9: 192.168.21.70-79) inter-...
user avatar
  • 552
1 vote
2 answers
116 views

Multicasting - How to send a hint to the router?

I found a multicasting example at http://ntrg.cs.tcd.ie/undergrad/4ba2/multicast/antony/example.html. After correcting some errors, this program seems to work fine within our network. I now need to ...
user avatar
1 vote
2 answers
999 views

IGMP Query Interval

What adverse effects could occurred if I set the igmp snooping querier query-interval to 1 second in the switch? The default in switch is 60 seconds
user avatar
  • 13
1 vote
0 answers
1k views

Cisco SG300 switch identifies itself as duplicate IP address

We've enabled IGMP snooping on one of our VLANs. The configuration used is: bridge multicast filtering ip igmp snooping ip igmp snooping vlan 1 ip igmp snooping vlan 1 querier We're now seeing the ...
user avatar
2 votes
2 answers
958 views

Multicasting questions

Ok, Basic question is this. show ip igmp snooping groups Is not returning the multicast groups I am creating More in-depth explanation. I want to test multicast. I am on a flat network, and I ...
user avatar
26 votes
1 answer
93k views

What are the benefits and cons of IGMP snooping?

Our new router is asking if we want IGMP snooping enabled. Not being familiar with this, I looked to the internet and got the following wiki description: IGMP snooping is the process of listening ...
user avatar
  • 363
6 votes
2 answers
1k views

IGMP Multicast router overrun

THE SYSTEM: I have a L2 Managed 1Gbps switch with IGMP snooping (the switch I'm testing with is a TP-Link TL-SG3216). I have several identical devices (these are embedded devices that we are ...
user avatar
  • 61
1 vote
1 answer
500 views

Is it possible to use group multicast (IGMP) over the internet?

I am looking at building an application that broadcasts audio using my own proprietary protocol. Under the covers I'd prefer to use IGMP or something where 1000 clients don't use 1000 times the ...
user avatar
2 votes
0 answers
276 views

Don't receive multicast traffic [closed]

I'm using multicast communications with IGMP snooping enable in the switch, I have 6 nodes (A, B, C, D, E, F), 3 sends data to different Multicast address and 3 receive data from every multicast ...
user avatar
  • 21
5 votes
3 answers
698 views

Multicast Distribution with PIM

I have to receive some multicast groups for an IPTV platform. I can't use PIM (they don't give me an RP address for the groups...). The provider suggested me to do a join to each multicast group and ...
user avatar
  • 501
9 votes
2 answers
7k views

why TTL value 1 in IGMP

why TTL value 1 in IGMP protocol and what are the different values possible in TTL section for Multicasting. What I got from the google is that if TTL value is 1 then it won't leave the LAN, but if ...
user avatar
3 votes
1 answer
1k views

Can we do destination port filtering in IGMP V2 or V3?

Is it possible to get a traffic from a multicast address with specific destination port using IGMP? For example, I have some multicast flows like 239.192.7.1:5000, 239.192.7.1:5001 to 239.192.7.1:5009....
user avatar
  • 31
10 votes
2 answers
5k views

KEMP load balancers using UCARP (VRRP) - multicast MAC address not being picked up

Alright - been battling this for at least 20 hours consecutive.. Sorry if this seems like a long rant, or a blog post, but I'm getting to the point of exhaustion. So, here's the deal. We're using KEMP ...
user avatar
  • 422